My primary research interests center around developing efficacious and effective behavioral interventions for substance use problems among adults with post-traumatic stress disorder (PTSD). Here, my clinical and research experiences have guided me to focus on smoking cessation. Clinically, I have observed that smoking is prevalent among patients who present for the treatment of PTSD, and that anxiety processes often serve to smoking. A growing body of research supports these observations. Moreover, extant smoking cessation interventions have often failed to yield lasting clinical change. These observations converge with one another to suggest that there is scientific and clinical merit to developing interventions that target anxiety processes and PTSD in one overarching model. My research experience to date is primarily in the area of the nature, causes, and treatment of anxiety disorders. Thus, my proposed line of research requires further training in substance use disorders. In the short- term, my professional goals provide clear direction for further training. would like to use the K01 mechanism to build upon my previous experience and training in three meaningful ways. First, I selected two mentors [Drs. Smits (Primary) and Zvolensky (Co-Mentor)] who can guide me in my efforts to develop an independent research program focusing on smoking cessation. Dr. Smits and Zvolensky bring expertise in the development and evaluation of interventions for anxiety and related substance use problems. Second, with help of Dr. Foa, an internationally-recognized expert in PTSD, I have developed a curriculum to build my expertise in PTSD. Third, I have planned a series of courses and meetings with Dr. Rosenfield, a biostatistician, to learn about statistical methods as it relates to testing mediatio and moderation. Together, these integrated training experiences will help me reach my long-term goal, which is to pursue this independent line of work as a tenured faculty member in a psychology department. The research plan of this K01 application is consistent with my transition to substance use disorder research. This K01 research plan aims to develop and test an integrated intervention for improving the outcome of cognitive-behavioral therapy (CBT) for smoking cessation in adults with PTSD. PTSD is associated with increased smoking and failed cessation attempts.2-7 The prevalence of smoking in persons with PTSD is 44.6 %, compared to 22.5% in persons with no psychiatric disorder.8 Smokers with PTSD are more likely to be dependent,4 smoke heavily (> 25 cigarettes per day),2 experience more severe withdrawal symptoms, and relapse following a quit attempt.2 In fact, the quit rate in smokers with PTSD (23.2%) is one of the lowest of all mental disorders.8Thus, the vast majority of persons with PTSD attempting to quit smoking do not benefit from existing intervention protocols. Clearly, there is a need for the development of specialized or personalized strategies for this population. Features of PTSD that may contribute to smokers' progression to nicotine dependence and cessation relapse include negative affect, fear, increased arousal, irritability, anger, distress intolerance, and anxiety sensitivity. Anxiety sensitivity is higher in persons with PTSD than in any other anxiety disorder except for panic disorder.9 High anxiety sensitivity is uniquely associated with greater odds of lapse10 and relapse11-13 during quit attempts.13 Distress intolerance, a perceived or behavioral tendency to not tolerate distress,14 is related to both the maintenance of PTSD and problems in quitting smoking.15 Fear extinction-based treatments (i.e., prolonged exposure [PE], interoceptive exposure [IE]) have shown efficacy for reducing PTSD16 and distress intolerance and anxiety sensitivity17-19 and therefore emerge as promising candidates to augment standard smoking cessation interventions for individuals with PTSD. The present application proposes to pilot test an integrated and specialized treatment for smokers with PTSD. This Integrated PTSD and Smoking Treatment (IPST) combines cognitive-behavioral therapy and nicotine replacement treatment for smoking cessation (standard care; SC) with PE to target PTSD symptoms (e.g., negative affect, fear, increased arousal, irritability, anger) and IE to reduce anxiety sensitivity and distress intolerance. To thi end, 80 adult smokers with PTSD will be randomly assigned to either: (1) IPST or (2) SC. Smoking outcomes will be assessed 2, 4, 8, 10, 16, and 24 weeks after quit date. Measure of putative mediators will be assessed repeatedly prior and following the quit date.